1. Field of the invention
This invention relates to a novel crystalline saccharide, and its production and use, more particularly, to a crystalline maltosyl glucoside, and its production and use.
2. Description of the prior art
Maltotriose is a tri-saccharide represented by the general formula of O-.alpha.-D-glucopyranosyl-1.fwdarw.4)O-.alpha.-D-glucopyranosyl-(1.fwdarw .4)D-glucopyranose, and has been known as a sweetener which can be incorporated into syrupy and powdery starch. This saccharide is characteristic of its low sweetness and used in compositions including beverages, foods and tastable products such as tobaccos and cigarettes.
Since maltotriose is a reducing saccharide, it has the drawbacks that it readily causes browning reaction along with proteins and amino acids contained in beverages and foods to readily induce the deterioration and degeneration of these products, and therefore the present inventors have studied means to overcome the drawbacks and found that the preparation of a non-reducing maltosyl glucoside from maltotriose is attained by exposing a reducing partial starch hydrolysate having a glucose polymerization degree of 3 or higher to the action of an enzyme capable of forming a non-reducing saccharide having a trehalose structure as an end unit (hereinafter called "a non-reducing saccharide-forming enzyme" in the present specification), those disclosed in Japanese Patent Application No. 349,216/93, however, the powdery non-reducing saccharide of maltosyl glucoside is amorphous and physically unstable, and, for the sake of stability, the establishment of a more stable crystalline maltosyl glucoside is expected.
On the other hand, as to maltosyl glucoside, for instance, conventional preparation methods as reported by Von Werner Fisher et al. in "Hoppe-Seyler's Zeitshrift fur Physiologishe Chemie", Vol.350, pp.1137-1147 (1969), methods for extracting from microorganisms, or in chemical synthetic methods as reported by Shinkiti Koto et al. in "Bulletin of Chemical Society of Japan", Vol.59, pp.411-414 (1986) as well as by Hans Peter Wessel et al. in "Helvetica Chimica Acta", Vol.74, pp.682-695 (1991), however, there is no report of and has been unknown a crystallization method for obtaining maltosyl glucoside.